Dispensing devices, discharging a predetermined amount of fluid product in a container when required, have been developed in a variety of types due to their convenience in use. One type of them is a manual pump-type dispenser that comprises cylinder, piston, spring, nozzle, etc. and is engaged to the upper of a container for use. The manual pump-type dispenser discharges a fluid product through the nozzle when the pump is pressed downwardly.
The other type of them is a dispensing closure with an automatic sealing valve. The dispensing closure discharges a fluid product through the automatic sealing valve that opens when a container is subjected to an external force, such as a squeezing force, and then automatically closes by the inherent resilience thereof when the external force is released. Such automatic sealing valves are disclosed in U.S. Pat. Nos. 1,607,993, 2,802,607, 3,257,046, etc.
Many structural configurations of the dispensing closure have been developed with these automatic sealing valves for more convenience in use. A representative example is disclosed in U.S. Pat. No. 5,271,531, issued on Dec. 21, 1993 to Rohr et al., entitled “DISPENSING CLOSURE WITH PRESSURE-ACTUATED FLEXIBLE VALVE,” which includes a cylindrical closure body, a flexible self-sealing valve (automatic sealing valve), a retaining ring, a central support member, etc. The retaining ring is adapted to be disposed in a collar of the closure body so as to prevent the self-sealing valve from being upwardly dislodged during operation. Also, the dispensing closure is provided with the central support member, having an upwardly facing concave surface that is surrounded by a flat, annular, peripheral surface, within a dispensing aperture for supporting the dispensing valve, thereby preventing the self-sealing valve from being downwardly dislodged during operation. However, this structural configuration has some drawbacks as below.
First, the structural configuration according to the above patent requires the retaining ring. Nevertheless, the possibility of dislodgement of the automatic sealing valve continuously exists because the self-sealing valve is so flexible that it can be too largely deformed during operation, thereby causing the upwardly dislodgement thereof. In particular, the dispensing closure with the automatic sealing valve is usually used in a reverse position, i.e., the opening thereof facing downwardly, and in this position, some fluid product in a container may enter the gap between the dispensing closure and the automatic sealing valve to help dislodgement of the valve by working as a lubricant. Moreover, where a defect occurs in the retaining ring in a manufacturing and/or assembling processes, it is very difficult to disassemble the retaining ring without causing any damage in the automatic sealing valve, because the retaining ring need to be strongly attached to the dispense closure for preventing the possibility of dislodgement as described above.
Second, the structural configuration according to the above patent also requires the separate, supporting member to prevent the automatic sealing valve from being downwardly dislodged during operation. The automatic sealing valve generally has the similar thickness through an opening of the closure body and thus the downward pressure is uniformly applied to the top surface of the valve, exposed through the opening, when the squeezing pressure is released. In other words, the downward pressure does not concentrate at a certain area of the automatic sealing valve, so that a relatively high force is applied to the portion between the closure body and the automatic sealing valve, which can cause the automatic sealing valve to be dislodged downwardly. As a result, the supporting member is required.
The need of the retaining ring and supporting member for configuration of dispensing closure causes complication of manufacturing and assembling steps, which also causes the possibility of its defect and disorder as well as the manufacturing cost to increase.
In accordance with the present invention, an automatic sealing dispensing closure is provided which substantially reduces or eliminates disadvantages and problems associated with prior art dispensing closures. That is, an object of the present invention is to provide a dispensing closure which can be actuated even without any separate retaining means and supporting means by making a closure body and automatic sealing valve in a special form so as to reduce the number of components and shorten the manufacturing and assembling processes. Another object of the present invention is to provide a dispensing closure that has an excellent sealing effect and very low possibilities of defects in manufacture and disorders during use.